U.S. patent application number 10/362251 was filed with the patent office on 2004-02-12 for method for classifying an obstacle by means of pre-crash sensor signals.
Invention is credited to Koehler, Armin, Loeckle, Gerhard, Moritz, Rainer, Oswald, Klaus, Roelleke, Michael.
Application Number | 20040030476 10/362251 |
Document ID | / |
Family ID | 7690761 |
Filed Date | 2004-02-12 |
United States Patent
Application |
20040030476 |
Kind Code |
A1 |
Oswald, Klaus ; et
al. |
February 12, 2004 |
Method for classifying an obstacle by means of pre-crash sensor
signals
Abstract
A method of classifying an obstacle on the basis of pre-crash
sensor signals is described, acceleration and acceleration change
being determined from the obstacle velocity, and the obstacle is
classified on the basis of these parameters. The deployment
algorithm is tightened as a function of this classification; if
appropriate, restraining means are deployed at an early stage and
an automatic braking and/or steering intervention takes place.
Inventors: |
Oswald, Klaus; (Wendlingen,
DE) ; Roelleke, Michael; (Hoefingen, DE) ;
Moritz, Rainer; (Filderstadt, DE) ; Loeckle,
Gerhard; (Ludwigsburg, DE) ; Koehler, Armin;
(Sachsenheim, DE) |
Correspondence
Address: |
KENYON & KENYON
ONE BROADWAY
NEW YORK
NY
10004
US
|
Family ID: |
7690761 |
Appl. No.: |
10/362251 |
Filed: |
June 17, 2003 |
PCT Filed: |
June 15, 2002 |
PCT NO: |
PCT/DE02/02189 |
Current U.S.
Class: |
701/45 ;
701/46 |
Current CPC
Class: |
B60R 21/34 20130101;
B60R 21/0134 20130101; B60R 21/013 20130101; B60R 2021/01259
20130101 |
Class at
Publication: |
701/45 ;
701/46 |
International
Class: |
G06F 007/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 5, 2001 |
DE |
101 32 681.5 |
Claims
What is claimed is:
1. A method of classifying an obstacle on the basis of pre-crash
sensor signals, a relative velocity between the vehicle and the
obstacle being determined from the pre-crash sensor signals, the
obstacle velocity being determined from the relative velocity and
the vehicle velocity, wherein an acceleration and an acceleration
change are determined from the obstacle velocity, and the obstacle
is classified on the basis of the acceleration, the acceleration
change and the obstacle velocity.
2. The method as recited in claim 1, wherein a deployment algorithm
for restraining means is adjusted as a function of the obstacle
classification.
3. The method as recited in claim 2, wherein restraining means are
deployed as a function of the adjustment of the deployment
algorithm prior to an impact with the obstacle.
4. The method as recited in claim 1, 2, or 3, wherein an automatic
braking intervention and/or steering intervention takes place as a
function of the obstacle classification.
5. The method as recited in one of the preceding claims, wherein
pedestrian protection means are deployed as a function of the
obstacle classification.
6. A device for implementing the method as recited in one of claims
1 through 4, wherein the device has at least a pre-crash sensor
(1), a processor (3) for analyzing the pre-crash signals, and
restraining means (6), provided the restraining means (6) are
connectable to the processor (3).
7. The device as recited in claim 6, wherein the device has an
actuator (8) for a braking intervention and/or a steering
intervention.
8. The device as recited in claim 5 and 6, wherein the device is
connectable to pedestrian protection means.
Description
BACKGROUND INFORMATION
[0001] The present invention is directed to a method of classifying
an obstacle on the basis of pre-crash sensor signals according to
the definition of the species in the independent claim.
[0002] The placement of radar sensors in side doors of a motor
vehicle in order to determine the velocity of an obstacle by using
these radar sensors as pre-crash sensors is known from German
Unexamined Patent Application 198 03 068 A. This makes it possible
to determine an ideal point in time for the deployment of side
airbags.
ADVANTAGES OF THE INVENTION
[0003] The method according to the present invention of classifying
an obstacle on the basis of pre-crash sensor signals having the
features of the independent claim has the advantage over the
related art of making an improved obstacle classification possible
by considering parameters such as obstacle velocity, acceleration,
and acceleration change. This makes optimum utilization of
restraining means possible since, by considering these parameters,
a more accurate estimation with regard to the type of a probable
obstacle is possible.
[0004] Advantageous improvements on the method of classifying an
obstacle on the basis of pre-crash sensor signals described in the
independent claim are possible by using the measures and
refinements listed in the dependent claims.
[0005] It is particularly advantageous that the deployment
algorithm for the restraining means has an improved deployment
performance due to the improved obstacle classification, which
makes an ideal point in time for deployment of the restraining
means possible. It is an additional advantage that the obstacle
classification makes an automatic braking or steering intervention
possible which is decided on the basis of different stored data.
This may then contribute to an accident avoidance.
[0006] Furthermore, it is an advantage that active pedestrian
protection is possible due to the improved obstacle classification,
since a pedestrian is identifiable as an obstacle, and thus
restraining means, for example, which are attached to the outer
shell of the vehicle, such as a pedestrian airbag, may be optimally
deployed.
[0007] Finally, it is also an advantage that a device for the
implementation of the method according to the present invention is
provided which has a processor for the implementation of the method
according to the present invention and which may be connected to an
actuator for the steering or braking interventions and to the
pedestrian protection means, i.e., the outer airbags.
DRAWING
[0008] Exemplary embodiments of the present invention are
illustrated in the drawing and are explained in greater detail in
the following description. FIG. 1 shows a block diagram of a device
according to the present invention, and FIG. 2 shows a flowchart of
the method according to the present invention.
DESCRIPTION
[0009] The severity of an accident caused by an impact is
determined by the type and the velocity of obstacles. According to
the present invention, an obstacle is classified on the basis of
pre-crash sensor signals by determining the obstacle velocity,
acceleration, and acceleration change. An ideal point in time for
the deployment of restraining means and the utilization of
pedestrian protection means or an active intervention in the
driving operation are thus ultimately possible for accident
avoidance.
[0010] FIG. 1 shows the device according to the present invention
in a block diagram. A pre-crash sensor 1 is connected to a data
input of a signal processing unit 2. Signal processing unit 2 is
connected to a processor 3 via a data output. Processor 3 is
connected to a memory 4 via a data input/output. Processor 1 is
connected to a signal processing unit 5 via a first data output.
Processor 3 is connected to a signal processing unit 7 via a second
data output. The data output of signal processing unit 5 is
connected to restraining means 6. The data output of signal
processing unit 7 is connected to an actuator 8. Actuator 8 is used
for active interventions in the driving operation, i.e., steering
intervention and/or braking intervention.
[0011] A radar sensor is used here as a pre-crash sensor
transmitting and receiving electromagnetic radiation in the
millimeter range. It is also possible to use an ultrasonic sensor
or a video sensor instead of a radar sensor. It is also possible to
utilize a plurality of such sensors, or even a combination of
different sensors.
[0012] Data from radar sensor 1, which outputs a digital data
stream which in turn is pre-processed for processor 3 by signal
processing unit 2, enables processor 3 to determine the velocity of
the obstacle. The relative velocity between the obstacle and the
vehicle is determinable from the pre-crash sensor signals. By
knowing the velocity of the vehicle itself, the velocity of the
obstacle toward the vehicle is now determinable. After an obstacle
has been detected by the vehicle, the pre-crash sensor may track
its further motion, i.e., a tracking of the object takes place. The
tracking data may then be used for the classification of the
object. By considering the vehicle velocity, the object velocity
and its change over time, i.e., the acceleration, may be
determined. The acceleration of the obstacle, as well as the
acceleration change of the obstacle is determinable via a
derivative of the velocity of the obstacle (=object) over time. The
distance traveled is determined by integration of the velocity of
the obstacle.
[0013] For its calculations processor 3 uses memory 4, in
particular for storing intermediate results. If the velocity of the
obstacle is zero, then it is presumably a stationary object and an
impact may be avoided via a simple steering intervention, for
example. At a low or non-existent velocity a braking intervention
may also take place depending on the probable braking distance.
[0014] However, if an impact is unavoidable, then appropriate
restraining means, such as airbags and seat belt tensioners, may be
deployed at an early stage in order to ensure passenger protection.
If the velocity amounts to a maximum of up to 30 km/h and the
acceleration is relatively low, then it can be assumed that the
obstacle is probably a pedestrian. It is possible here to lower the
velocity limit even further, since only few pedestrians are able to
reach 30 km/h.
[0015] If an impact on the pedestrian can no longer be avoided,
then outer airbags may be triggered for the pedestrian in order to
provide optimum protection for the pedestrian and to minimize
injuries.
[0016] In general, if an impact can no longer be avoided, the
appropriate thresholds in the deployment algorithm for the
restraining means, calculated in processor 3, are lowered in order
to achieve tightening of the deployment algorithm so that, even in
the case of measuring signals having a low amplitude, the
deployment algorithm indicates deployment of restraining means
6.
[0017] If it has been determined that there is neither a fixed
obstacle nor a pedestrian, but a vehicle, then appropriate steering
interventions and/or restraining means are utilized.
[0018] FIG. 2 shows the method according to the present invention
in a flow chart. In method step 9, the pre-crash signals are picked
up by pre-crash sensor 1 and transmitted in the form of digital
data to signal processing unit 2 which prepares the data for
processor 3. Processor 3 calculates velocity, acceleration, and
acceleration change in method step 10. The obstacle classification
takes place on the basis of these parameters.
[0019] It is now checked in method step 11 whether there is a fixed
object according to the obstacle classification. If this is the
case, then appropriate protective measures take place in method
step 12, i.e., either a steering intervention, or an early
deployment of restraining means, but the deployment thresholds in
the deployment algorithm are always lowered in order to achieve
tightening of the deployment algorithm.
[0020] If it has been determined in method step 11 that there is no
fixed object, then it is checked in method step 13 whether the
obstacle classification, i.e., method step 10, has identified a
pedestrian. If this is the case, then an appropriate protective
measure is implemented in method step 14, i.e., either an evasion
maneuver or triggering of an outer airbag.
[0021] If it has been determined in method step 13 that there is
neither a pedestrian nor a fixed obstacle, but a moving object,
i.e., a vehicle, then appropriate protective measures are
implemented in method step 15, i.e., tightening of the deployment
algorithm and, as the case may be, the early triggering of
restraining means, or active interventions in the driving
operation, i.e., steering interventions or braking interventions.
Actuator 8 is utilized for this purpose.
* * * * *